1. Field of the Invention
The present invention relates to generation of multi-phase clocks, and more particularly, to a multi-phase clock generator utilized in a network controller and method thereof.
2. Description of the Prior Art
Multi-phase clock generators are devices utilized to produce multiple clocks having the same frequency but different phases. Typically, the different clock signals produced by multi-phase clock generators can be referred to as a set of multi-phase clocks. The production of multi-phase clocks is an important task when proceeding with the control of slew rate.
Network controllers often produce multi-phase clocks by utilizing multi-phase clock generators. An Ethernet transmitter, for example, operating under 10M mode, requires multi-phase clocks with frequencies of 250 MHz, duty cycles of 50%, and the phase difference between any two adjacent clocks must be one nanosecond. Additionally, under Giga/100M, the Ethernet transmitter requires multi-phase clocks with frequencies of 125 MHz, duty cycles of 25%, and the phase difference between any two adjacent clocks must be one nanosecond.
Usually, network controllers will produce the multi-phase clocks by utilizing phase lock loop or delay lock loop. Unfortunately, both of these methods, to produce the multi-phase clocks, require complex circuit architecture and consume significant power.